From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754591AbdL1RrW (ORCPT ); Thu, 28 Dec 2017 12:47:22 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:60175 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751837AbdL1Rco (ORCPT ); Thu, 28 Dec 2017 12:32:44 -0500 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Casey Schaufler" , "Kees Cook" , "Eric W. Biederman" , "Linus Torvalds" , "Willy Tarreau" , "Oleg Nesterov" , "James Morris" , "Jann Horn" , "Ingo Molnar" , "Andy Shevchenko" , "Al Viro" , "Andy Lutomirski" , "Serge E. Hallyn" Date: Thu, 28 Dec 2017 17:05:44 +0000 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 194/204] security: let security modules use PTRACE_MODE_* with bitmasks In-Reply-To: X-SA-Exim-Connect-IP: 2a02:8011:400e:2:6f00:88c8:c921:d332 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.52-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Jann Horn commit 3dfb7d8cdbc7ea0c2970450e60818bb3eefbad69 upstream. It looks like smack and yama weren't aware that the ptrace mode can have flags ORed into it - PTRACE_MODE_NOAUDIT until now, but only for /proc/$pid/stat, and with the PTRACE_MODE_*CREDS patch, all modes have flags ORed into them. Signed-off-by: Jann Horn Acked-by: Kees Cook Acked-by: Casey Schaufler Cc: Oleg Nesterov Cc: Ingo Molnar Cc: James Morris Cc: "Serge E. Hallyn" Cc: Andy Shevchenko Cc: Andy Lutomirski Cc: Al Viro Cc: "Eric W. Biederman" Cc: Willy Tarreau Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Ben Hutchings --- security/smack/smack_lsm.c | 8 +++----- security/yama/yama_lsm.c | 4 ++-- 2 files changed, 5 insertions(+), 7 deletions(-) --- a/security/smack/smack_lsm.c +++ b/security/smack/smack_lsm.c @@ -163,12 +163,10 @@ static int smk_copy_rules(struct list_he */ static inline unsigned int smk_ptrace_mode(unsigned int mode) { - switch (mode) { - case PTRACE_MODE_READ: - return MAY_READ; - case PTRACE_MODE_ATTACH: + if (mode & PTRACE_MODE_ATTACH) return MAY_READWRITE; - } + if (mode & PTRACE_MODE_READ) + return MAY_READ; return 0; } --- a/security/yama/yama_lsm.c +++ b/security/yama/yama_lsm.c @@ -292,7 +292,7 @@ int yama_ptrace_access_check(struct task return rc; /* require ptrace target be a child of ptracer on attach */ - if (mode == PTRACE_MODE_ATTACH) { + if (mode & PTRACE_MODE_ATTACH) { switch (ptrace_scope) { case YAMA_SCOPE_DISABLED: /* No additional restrictions. */ @@ -318,7 +318,7 @@ int yama_ptrace_access_check(struct task } } - if (rc) { + if (rc && (mode & PTRACE_MODE_NOAUDIT) == 0) { printk_ratelimited(KERN_NOTICE "ptrace of pid %d was attempted by: %s (pid %d)\n", child->pid, current->comm, current->pid);